138442230 has 64 divisors (see below), whose sum is σ = 381931200. Its totient is φ = 35642880.

The previous prime is 138442217. The next prime is 138442231. The reversal of 138442230 is 32244831.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 138442194 and 138442203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138442231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1011 + ... + 16670.

It is an arithmetic number, because the mean of its divisors is an integer number (5967675).

Almost surely, 2^138442230 is an apocalyptic number.

138442230 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 138442230, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (190965600).

138442230 is an abundant number, since it is smaller than the sum of its proper divisors (243488970).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

138442230 is a wasteful number, since it uses less digits than its factorization.

138442230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17726 (or 17720 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 138442230 is about 11766.1476278347. The cubic root of 138442230 is about 517.3163389431.

The spelling of 138442230 in words is "one hundred thirty-eight million, four hundred forty-two thousand, two hundred thirty".